The Powerblanket GHT2002J digital controller is a 120V regulator allowing for precise temperature control. Included are several disposable probes allowing for pinpoint (+/- 2F) temperature control. When deciding which blanket to order with your thermostat controller - always order a Powerblanket with a maximum temperature higher that you actually need. For example, if you are trying to bring water to a temperature of 80F in a 55 gallon drum, you need to order the Powerblanket BH55RR (100F) blanket which you can then adjust down to the desired 80F target temperature.